Portugal
Lisbon in September: weather, sea & travel advice
This month's data profile
Strong month under the current formula
Lisbon in September is climatically well suited to city breaks, active holidays and hiking, family holidays and beach holidays. The average daily high is around 22 °C, and the sea is about 19 °C. With about 5 rainy days it is dry.
Historical monthly averages, not a weather forecast. Individual days and years can differ substantially.
Rank among 12 monthly averages
81/100 · #3
Warmth
#3
Dryness
#4
Sun
#6
Sea warmth
#1
Published best categories: Overall, Beach, City break, Family
Lisbon · SeptemberPhoto: Dale Cruse - 10M views from San Francisco, CA, USA · CC BY 4.0Climate facts
- Average high
- 22 °C
- Average low
- 18 °C
- Sea
- 19 °C
- Rainy days (est.)
- 5 rainy days (est.)
- Sun (est.)
- 7 h/day
- Humidity
- 81 %
For your trip planning
September: city stay with a beach option
Our series gives September fewer rainy days than October and warmer water than June. Compare them directly for a mixed city-and-beach itinerary. This promises neither rain-free sightseeing nor water that everyone finds warm enough.
Climate evidence with direct month comparison
The highlighted row is the selected month. Precipitation total and rainy days are separate monthly averages.
| Month | Avg high °C | Avg low °C | Rainy days (est.) | Precipitation mm | Sun h/day (est.) | Humidity % | Wind m/s | Sea °C | Score |
|---|---|---|---|---|---|---|---|---|---|
| August | 23 | 18 | 1 | 5 | 8.3 | 81 | 4.5 | 19 | 84 |
| September (selected) | 22 | 18 | 5 | 28 | 6.6 | 81 | 4.0 | 19 | 81 |
| October | 21 | 17 | 10 | 76 | 4.5 | 81 | 4.2 | 18 | 66 |
How do the previous and next months compare?
Baseline: September (81/100)
Positive and negative values show the change from the selected month.
| Score Δ | Average high Δ | Average low Δ | Rainy days Δ | Rain Δ | Sun Δ | Humidity Δ | Wind Δ | Sea Δ | |
|---|---|---|---|---|---|---|---|---|---|
| August | +3 | +0.9 °C | +0.4 °C | -4 | -22.7 mm | +1.7 h | -0.4 % | +0.4 m/s | -0.1 °C |
| October | -15 | -1.8 °C | -1.3 °C | +5.2 | +48.3 mm | -2.1 h | +0.5 % | +0.2 m/s | -0.5 °C |
All twelve months in context
Find a place to stay
Where to stay in Lisbon
Compare available stays, prices and cancellation terms for Lisbon on Booking.com.
Booking.comFind places to stayAffiliate link: there is no extra cost to you.
Useful next decisions
Frequently asked questions
How warm is Lisbon in September?
The average daily high is around 22 °C, with an average daily low of about 18 °C.
Can you swim in Lisbon in September?
The sea is about 19 °C (refreshing).
Does it rain a lot in Lisbon in September?
The curated estimate is about 5 rainy days per month, not a directly measured long-term average. Total precipitation averages around 28 mm for the month. A rainy day does not mean all-day rain.
When is the best time to visit Lisbon?
By the climate score, June, July, August and September are the strongest months for Lisbon. For a beach trip: June, July, August and September. September is one of them.